ART-E theory: Perceived depth and width is a function of visual angle ratio and elevation

An illusion analogous to Cornsweet's is used to demonstrate how the non-linear behavior of the visual system can be used to obscure low-frequency gradients. The result is a reversal of brightness—from light to dark—as the visual angle of the display is changed.

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Letter Identification in Words and Non-Words, with Variation in Visual Angle and Delay of Position Cue

Perception ◽

10.1068/p110305 ◽

1982 ◽

Vol 11 (3) ◽

pp. 305-317 ◽

Cited By ~ 4

Author(s):

Robert T Solman

Keyword(s):

Serial Position ◽

Letter String ◽

Visual Angle ◽

Superior Performance ◽

Word Superiority Effect ◽

Letter Identification ◽

Superiority Effect ◽

Critical Letter ◽

Contextual Constraint ◽

Perceptual Locus

Two experiments are described in which subjects were required to report the name of a single position-cued ‘critical’ letter in a tachistoscopically displayed string of four letters. The stimulus characters were arranged to form three types of letter strings: (i) strings in which the letters did not form words; (ii) words in which contextual constraint of the critical letters was minimised; and (iii) words in which contextual constraint of the critical letters was maximised. The serial position of the letter to be identified in each string was cued at delays of −500, −100, and +500 ms, in experiment 1 and at delays of −510 and +510 ms in experiment 2, and in both experiments one group of subjects responded to letter strings which subtended a horizontal visual angle of 3·95 deg, while a second group responded to strings which subtended 1·02 deg. Correct identifications of critical letters showed that the presentation of words resulted in superior performance. This ‘word superiority effect’ is consistent with earlier findings implying that it has a perceptual locus. For the stimuli which subtended the large visual angle the word advantage was detrimentally affected only when the position of the critical letter to be identified was cued either 500 or 510 ms prior to the display of the letter string.

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The Discussion on the Construction of City Waterfront Landscape Based on the Visual Angle of Ecology Restoration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.6827 ◽

2011 ◽

Vol 243-249 ◽

pp. 6827-6833 ◽

Cited By ~ 1

Author(s):

Gui Yuan Li ◽

Zhong Yuan Duan ◽

Yang Xu

Keyword(s):

Climate Change ◽

Global Climate Change ◽

Visual Angle ◽

Global Climate ◽

Optimization Method ◽

Water Shortage ◽

Practical Significance ◽

Living Standard ◽

Design Technique ◽

The Sustainable Development

In recent years, with the increase of population, the development of urbanization, and the improvement of people’s living standard, people have got an increasingly strong consciousness of environment landscape. While, the global climate change, water shortage and pollution problems which are resulted in the development of social economy.In this article, according to the different traits of waterfront landscape environment, we will analyze the problems of waterfront landscape environment construction, and discuss the design technique of waterfront landscape and the optimization method of landscape environment based on the visual angle of ecology restoration. This can prompt the development of waterfront landscape environment towards the harmony and intergrowth of nature ,ecology and human culture, and this has practical significance for the sustainable development of human and water.

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The visually controlled prey-capture behaviour of the European mantispid Mantispa styriaca

Journal of Experimental Biology ◽

10.1242/jeb.203.14.2117 ◽

2000 ◽

Vol 203 (14) ◽

pp. 2117-2123 ◽

Cited By ~ 4

Author(s):

K. Kral ◽

M. Vernik ◽

D. Devetak

Keyword(s):

Visual Angle ◽

Prey Capture ◽

Critical Value ◽

Midsagittal Plane ◽

Praying Mantis ◽

Binocular Field ◽

Video Frames ◽

Field Of Vision ◽

Left And Right ◽

Predatory Insects

Mantispids (Mantispa styriaca) are predatory insects; on bright sunny days, they wait in ambush for insect prey. The prey is captured as soon as it is within reach by means of lightning-speed strikes with the powerful forelegs. The strikes can take less than 60 ms. The mantispid accomplishes this almost as effectively as the larger praying mantis, which occupies a similar habitat, even though the praying mantis has apposition eyes with a high-resolution fovea, whereas the mantispid has unspecialized optical superposition eyes. Mantispa styriaca reacts to an item of prey when the latter covers a critical visual angle. The detection of prey immediately triggers adjustment reactions in the mantispid, which attempts to position the prey item in the visual field of both eyes and in the capture zone. Irrespective of the size of the prey, the capture reaction of the mantispid is always triggered if the distance to the prey falls below a certain critical value. As indicated by the analysis of individual video frames, immediately before an aimed strike, the item of prey is always positioned exactly in the centre of the binocular field of vision in the extended midsagittal plane of the mantispid's head. The strike may be triggered by the ommatidia of the left and right eyes, the lines of sight of which converge precisely on this region. The principal conclusion to be drawn is that the prey-capture behaviour of the mantispid appears to be based on a triangulation mechanism.

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The Relationship between Institutional Environment and Enterprise’s Technology Innovation Performance——The Visual Angle Based on MOA Theoretical Model

MATEC Web of Conferences ◽

10.1051/matecconf/201710005027 ◽

2017 ◽

Vol 100 ◽

pp. 05027

Author(s):

Shuying Wang ◽

Xingye Xiao

Keyword(s):

Theoretical Model ◽

Visual Angle ◽

Technology Innovation ◽

Institutional Environment ◽

Innovation Performance ◽

The Relationship

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Vicario's Illusion of Sloping Steps Reexamined

Perception ◽

10.1068/p160671 ◽

1987 ◽

Vol 16 (5) ◽

pp. 671-675

Author(s):

Paola Bressan

Keyword(s):

Visual Field ◽

Visual Angle

If a few parallel horizontal rows of dots are set diagonally, like steps, across the visual field, the inner rows appear not to be horizontal but sloping up to one side; the effect holds as long as the vertical distances between the rows do not exceed a given visual angle. This illusion, described by Vicario in 1978, was never explained. An experiment is reported in which the illusion was still visible at row separations well in excess of the spatial limits originally considered, provided the stimulus elements were enlarged. The maximum illusion was obtained for length ratios (interrow distance to size of dots) identical to those which have been shown to produce the largest effects in a number of illusions of area and length. This suggests that Vicario's illusion is similar to other illusions of extent, and that it can be explained by a neural extent-coding model.

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